Illinois Home Inspector Practice Exam

What is the typical lifespan of horizontal cast iron pipe?

1. 20 to 30 years

2. 30 to 40 years

3. 40 to 50 years

4. 50 to 60 years

The correct answer is: 40 to 50 years

The typical lifespan of horizontal cast iron pipe is often considered to be 40 to 50 years due to several factors that influence its durability and performance. Cast iron pipe has historically been used for its strength and resistance to high pressures and temperatures, making it a popular choice for sewage and drainage systems. Over time, however, the pipe can experience corrosion, particularly from the inside due to the chemicals in wastewater and environmental conditions. Factors such as soil composition, moisture levels, and the presence of aggressive chemicals can also affect the rate of deterioration. Having a lifespan of 40 to 50 years accounts for these various influences while still recognizing the inherent durability of cast iron. While some cast iron pipes can last longer, ongoing maintenance and inspections are crucial in determining their condition and lifespan, as many older systems may develop issues over time that necessitate replacement earlier than the expected lifespan. This context helps clarify why the choice of 40 to 50 years is widely accepted as typical for horizontal cast iron pipe.